[soulboy]

The pic speaks for itself. I was attempting to reinstall it in a 7S36b movement, and decided to pull it out to have another attempt. The balance wheel caught on the movement as I pulled (not gently enough obviously) and here is the result. Has anyone attempted to put a new spring and balance (Seiko part# 0311 050) on to a balance cock before? How difficult was it?

 

[LongBike]

I Have done it .......

I have done that a couple times, but lucky with old ones and have to
use a good Lupe or a good Magnifying Glass. But to be extremely careful
of all this they should be mounted if holding the parts.
I have also done it with a Hobby Head Magnifing Glass ,
and been successful also.
It takes quite a steady hand to set it right at first trying,
then comes the locking screw. Using a good light was very,
very helpful. After the first one, I decided to get a good strong
" LED TYPE " hanging light for my room corner ceiling.
Very powerful , but no heat exposure.
My Electrician friend made this for me and one other type also
mounted in a Plexi-Glass housing and its height adjustable also.
Should have done that in the first place but did not know about
it being ............ ( Really Extremely Necessary to have. )

 

[melt]

Has anyone attempted to put a new spring and balance (Seiko part# 0311 050) on to a balance cock before? How difficult was it?
View attachment 88498

Never because I know its 100 times more fiddly than putting the balance back in. We need some instruction from the maestro Joe Horner in this department.

 

[7s26b]

The 6R15 tech pdf has a good illustrated section on balance fitting/removal and this site is invaluable for 7s movements repair http://www.clockmaker.com.au/diy_seiko_7s26/chapter9.html

 

[ivorbiggin]

Ive done that on more than one occasion.
I have found the simple solution to a damaged hairspring, is to buy a dozen movements from Ramon the watch collector.
Study the pics real hard, theres usually 2 or 3 balance assy's that are salvageable.

 

[Joe Horner]

Thanks Melt, but 7s26b beat me to it - that page from the tech guide really says all you need to know for fitting these. Obvioously, it can't show you how to avoid slipping as you do it, but that method with care and a steady hand is all here is to it

 

[LongBike]

Thats it Sir

Have to be in good positon, concentration, and paying asttention
to what is being done. Can't grab any Beers, food,Coffee
or likeness, or it will be a disaster. And other people around
bothering. A clean work bench is a must to have.:72:

 

[xzqt]

The pic speaks for itself. I was attempting to reinstall it in a 7S36b movement, and decided to pull it out to have another attempt. The balance wheel caught on the movement as I pulled (not gently enough obviously) and here is the result. Has anyone attempted to put a new spring and balance (Seiko part# 0311 050) on to a balance cock before? How difficult was it?
View attachment 88498

Ohh dear.
Looks like a new balance is needed.

 

[Joe Horner]

Have to be in good positon, concentration, and paying asttention
to what is being done. Can't grab any [...] Coffee [...]

Do NOT let me near your watch until at least my 3rd coffee of the day - it'll end in tears if you do

eta: On the other hand, after the 4th or 5th I'll have a good shot at straightening the spring in that photo for you

 

[croolis]

... ooops ... and do call it a balance bridge for decency's sake

 

[Joe Horner]

But it's not a bridge unless it's supported at both ends

 

[soulboy]

Thank you all for your responses. To address a few of them:

Using a good light was very, very helpful.

Couldn't agree more, Longbike.

The 6R15 tech pdf has a good illustrated section on balance fitting/removal and this site is invaluable for 7s movements repair http://www.clockmaker.com.au/diy_sei.../chapter9.html

7s26b, thanks very much for that link to the manual. I have been referring to the same website for disassembly of the movement and it has been very helpful. I met the man behind the site (Nick Hacko) last week at a presentation he gave in his shop about how time is measured. It was a fascinating presentation and Nick is a great guy.

ooops ... and do call it a balance bridge for decency's sake

The tech guide says balance cock.

 

[soulboy]

Something you need to know if using the Time Module Inc (Seiko international brand) technical manual to order parts. The part number given for the balance with stud and hairspring is 0311 050. After calling the local parts supplier they have no record of this number on the official Seiko database and instead have it as 0310 020. The price is $12 AUD.

 

[soulboy]

Update - replacing the balance

After buying a new balance and spring assembly, I removed the old one off the balance cock according to the instructions in the 7s26 technical guide. Here's a pic before I removed it (I held a loupe against the lens of my camera to get enough magnification, hence the poor quality):

Removal was pretty straightforward. The brass stud in the regulator arm is held in by friction so you just pull it out. I wasn't looking forward to pushing the new one in.

I sat the new balance in the jewel, then screwed on the balance cock. NOw I needed to simply push the brass stud back in to the regulator arm and it's done. Here is what that looks like. You can see the brass stud sitting under the slot in the regulator arm...

On my first attempt, I didn't push completely straight and the regulator arm moved from the force against it while pushing the stud. My heart stopped, as any false move would destroy the hairspring again. It was going to require a lot of force applied at exactly the right time in the right direction. I'm very glad I heeded Longbike's advice and didn't drink any coffee for about 5 hours. It made a difference. Thanks Longbike! I also moved very slowly and breathed slowly.

At this point, I decided to leave it and come back for another go tomorrow. I wanted to be calm while I did it, and I think with each consecutive attempt in the same day your chances of damaging something increase.

More to come...

 

[BenchGuy]

The regulator system is essentially the EtaChron system. There are two tools...one for manipulating the regulator...one for removal of the stud. In the absence of these tools, the method you are undertaking may work...however, it looks like there is a strong likelihood of introducing a twist to ths hs when you attempt to press the stud back onto the holder. Removal of the stud is generally accomplished with a 90 degree twist of the stud...then it slips out of the holder...installation is the reverse. Hope that helps. Regards, BG

 

[xzqt]

I learn something,too, BG.

 

[7s26b]

Something you need to know if using the Time Module Inc (Seiko international brand) technical manual to order parts. The part number given for the balance with stud and hairspring is 0311 050. After calling the local parts supplier they have no record of this number on the official Seiko database and instead have it as 0310 020. The price is $12 AUD.

0310020 is the 7S26A part number, 0310197 is for the 7S26B/C.

 

[soulboy]

0310020 is the 7S26A part number, 0310197 is for the 7S26B/C.

Correct. It turns out I was sold the wrong part so I exchanged it for the correct one on the same day. One of the advantages of dealing with a bricks and mortar store instead of online.

 

[soulboy]

Update and finale

Hi all,

After a month away from watch tinkering I had the house to myself and decided to come back for another attempt.

Instead of trying to reattach the balance while it was sitting in the movement, I decided to take the balance cock and balance off and attach it sans movement. This gave me greater access from more angles and also allowed more light on the works.

I laid both pieces on a clean white piece of paper with the balance cock upside down ie. sitting on the top surface (as you look at the movement) like so...

Then I sat the balance on top. With my left hand I would hold it still with some tweezers like this:

At first everything went well. I went very slowly and carefully and managed to get the stud partially in to the groove (as I am typing, I just read Benchguys post saying installation is by a 90 degree twist. I have paid heavily for not reading this carefully before I launched in to this project again).

I was almost there. With a little more pressure I would have the stud in and the hairspring on the regulator. I'll let the pics do the talking again:

As you can see, the stud has been pushed completely off the hairspring; probably from a combination of clumsiness and poor installation technique. At this stage I have to throw in the towel and admit defeat. I'm left with this:

I'm not willing to continue to spend money on this movement (although it's not much money at all compared to Swiss parts if you can buy them) and parts if I'm going to continuously destroy them. I think I was a little ambitious this time, but I had managed to reassemble everything else without a problem so I was truly on the home straight. Oh well, I guess I have a 7S26 movement I can cannibalise sometime in the future. Unless someone want to buy it - it's got a brand new mainspring and barrel in it...

Thanks for reading and I hope you learned something from my experience. Oh - read do what Benchguy says if you find yourself in the same predicament.

 

[xzqt]

Guess the work is not so much for novice.
Buy a complete 7s26 with the money rather.